Initial data commit

Task/Parsing-RPN-calculator-algorithm/Python/parsing-rpn-calculator-algorithm-1.py

@@ -0,0 +1,59 @@
+def op_pow(stack):
+    b = stack.pop(); a = stack.pop()
+    stack.append( a ** b )
+def op_mul(stack):
+    b = stack.pop(); a = stack.pop()
+    stack.append( a * b )
+def op_div(stack):
+    b = stack.pop(); a = stack.pop()
+    stack.append( a / b )
+def op_add(stack):
+    b = stack.pop(); a = stack.pop()
+    stack.append( a + b )
+def op_sub(stack):
+    b = stack.pop(); a = stack.pop()
+    stack.append( a - b )
+def op_num(stack, num):
+    stack.append( num )
+
+ops = {
+ '^': op_pow,
+ '*': op_mul,
+ '/': op_div,
+ '+': op_add,
+ '-': op_sub,
+ }
+
+def get_input(inp = None):
+    'Inputs an expression and returns list of tokens'
+
+    if inp is None:
+        inp = input('expression: ')
+    tokens = inp.strip().split()
+    return tokens
+
+def rpn_calc(tokens):
+    stack = []
+    table = ['TOKEN,ACTION,STACK'.split(',')]
+    for token in tokens:
+        if token in ops:
+            action = 'Apply op to top of stack'
+            ops[token](stack)
+            table.append( (token, action, ' '.join(str(s) for s in stack)) )
+        else:
+            action = 'Push num onto top of stack'
+            op_num(stack, eval(token))
+            table.append( (token, action, ' '.join(str(s) for s in stack)) )
+    return table
+
+if __name__ == '__main__':
+    rpn = '3 4 2 * 1 5 - 2 3 ^ ^ / +'
+    print( 'For RPN expression: %r\n' % rpn )
+    rp = rpn_calc(get_input(rpn))
+    maxcolwidths = [max(len(y) for y in x) for x in zip(*rp)]
+    row = rp[0]
+    print( ' '.join('{cell:^{width}}'.format(width=width, cell=cell) for (width, cell) in zip(maxcolwidths, row)))
+    for row in rp[1:]:
+        print( ' '.join('{cell:<{width}}'.format(width=width, cell=cell) for (width, cell) in zip(maxcolwidths, row)))
+
+    print('\n The final output value is: %r' % rp[-1][2])

Task/Parsing-RPN-calculator-algorithm/Python/parsing-rpn-calculator-algorithm-2.py

@@ -0,0 +1,6 @@
+a=[]
+b={'+': lambda x,y: y+x, '-': lambda x,y: y-x, '*': lambda x,y: y*x,'/': lambda x,y:y/x,'^': lambda x,y:y**x}
+for c in '3 4 2 * 1 5 - 2 3 ^ ^ / +'.split():
+    if c in b: a.append(b[c](a.pop(),a.pop()))
+    else: a.append(float(c))
+    print c, a